N-Acetylcysteine Provides Analgesic Effect in Rats

N-acetylcysteine (NAC), an acetylated variant of L-cysteine, is commonly used as an antidote for acetaminophen overdose and antimucolytic agent in chronic obstructive pulmonary disease. Recently, NAC is found to have anti-inflammatory and antioxidant properties. The aim of the present study was to evaluate the analgesic effect of NAC in rat model of plantar test.

Male Wistar rats were randomly divided into six groups (n = 8). Animals received either normal saline (1 ml/kg) or different doses of NAC (200, 400, 600 mg/kg), morphine (10 mg/kg), or acetaminophen (50 mg/kg) intraperitoneally and the analgesic effect was assessed by plantar test apparatus at baseline, 30, 60 and 120 minutes after drug or vehicle administration.

NAC provided significant analgesia at 30 minutes post-administration compared to control (normal saline) group while in the other time points, there were no significant differences between NAC and control group in plantar test.

We found that NAC had analgesic effect and in order to find the involved mechanisms, further studies are needed.